Researchers at the National Cancer Center (NCC) have confirmed that taking calcium drugs, widely used for the prevention and treatment of osteoporosis, can increase the risk of cardiovascular diseases, such as angina and myocardial infarction.
The team, led by Professor Myung Seong-kwon, conducted a meta-analysis of 13 clinical trials published in international journals from 1990 to 2013.
Professor Kim Hong-bae of Myongji Hospital also participated in the study.
An analysis of the result showed that the risk of cardiovascular disease, including coronary artery disease and cerebrovascular disease, was 15 percent higher in patients taking calcium drugs than those taking placebos.
When the team divided the meta-analysis results by cardiovascular disease -- coronary artery disease and cerebrovascular disease -- only the risk of coronary artery disease was statistically significantly higher. In the case of subjects with underlying diseases, there was no statistical significance between the use of calcium drugs and cardiovascular disease risk.
However, the team confirmed that the risk of cardiovascular disease was statistically significantly increased in healthy postmenopausal women.
Currently, medical professionals recommend that adults over 50 years of age consume 700-1,200 mg (mg) of calcium a day to prevent and treat osteoporosis. They also recommend patients take calcium supplements if they do not get enough calcium from food. However, such a recommendation has recently become controversial. Some studies suggest that calcium drugs increase the risk of myocardial infarction, while some show no relationship between the drug and cardiovascular disease risks.
“Among the reasons the research results of meta-analysis papers are different are the selection criteria of individual papers included in the meta-analysis, the characteristics of the research subjects, and the inclusion of unpublished data,” Professor Myeong said.
Myeong explained that his study used biological mechanisms as the basis and confirmed that calcium supplements increase the serum calcium concentration, increasing the risk of calcification of blood vessels and leading to cardiovascular disease.
Professor Kim also said, “This study is a comprehensive meta-analysis including the most clinical trials among meta-analysis papers published to date.”
As a result of conducting a meta-analysis by various factors such as cardiovascular disease type, subject characteristics, sex, age, region, duration of administration, dose, and quality of the study, the team found that the use of calcium drugs increased the risk of cardiovascular disease by about 15 percent, Kim added.
The results of the study were published in the journal, Nutrients.